For a wide landscape photograph where you want everything from the closest foreground element to the distant mountains to be as sharp as possible, which focus technique would an expert employ using a manual camera app?

The expert would employ the technique of hyperfocal distance focusing combined with a small aperture. This method is used to maximize the depth of field, which is the range of distances in a photograph where subjects appear acceptably sharp. To achieve sharpness from the closest foreground to the distant mountains, the goal is to extend this sharp range as much as possible.

First, the expert would select a small aperture. The aperture is the opening within the lens that controls the amount of light entering the camera. A smaller aperture, which corresponds to a larger f-number such as f/11 or f/16, increases the depth of field. This means more of the scene, both in front of and behind the precise focus point, will appear sharp. While extremely small apertures like f/22 further increase depth of field, they can introduce diffraction, an optical phenomenon where light waves spread out as they pass through a small opening, which can slightly reduce overall image sharpness. Therefore, an expert typically chooses an aperture like f/11 or f/16 to balance extensive depth of field with optimal clarity, avoiding excessive diffraction.

Next, using the manual camera app, the expert would manually set the focus point to the hyperfocal distance. The hyperfocal distance is the closest distance at which a lens can be focused while simultaneously rendering objects at infinity, meaning extremely far away, acceptably sharp. When the lens is precisely focused at this hyperfocal distance, everything from half of that distance to infinity will be acceptably sharp. This specific distance is not fixed; it varies depending on the lens's focal length, the chosen aperture, and the camera's sensor size. An expert might determine this distance using an in-app hyperfocal calculator, a separate hyperfocal distance application, or by referring to a printed chart. Manual camera apps provide precise control over the focus point, allowing the user to dial in the exact hyperfocal distance with accuracy.

For example, if the calculated hyperfocal distance for the specific lens and aperture combination is 3 meters (approximately 10 feet), the expert would manually set the focus of the lens precisely at 3 meters. This would ensure that everything from 1.5 meters (half of 3 meters) all the way to the distant mountains (infinity) appears sharp in the final photograph. Simultaneously, to ensure the highest image quality and minimal noise, the lowest possible ISO setting, such as ISO 100, would be selected. The shutter speed would then be adjusted accordingly to achieve proper exposure, often necessitating the use of a tripod due to the potentially slow shutter speeds resulting from the small aperture and low ISO.